lg_collision_detect.c File Reference

Functions
LG_BBox	lg_bbox (float min_x, float max_x, float min_y, float max_y, float min_z, float max_z)
LG_BBox	lg_bbox_from_cuboid (LG_Cuboid *cuboid)
LG_Cuboid	lg_cuboid_from_bbox (LG_BBox bbox, LG_Color_u c)
LG_BBox	lg_bbox_from_mesh (LG_Mesh *mesh)
LG_BBox	lg_bbox_transform (LG_BBox bbox, mat4_t matrix)
vec3_t	lg_bbox_get_center (LG_BBox *bbox)
zboolean	lg_bboxes_collide (LG_BBox *bbox1, LG_BBox *bbox2)
zboolean	lg_bbox_sets_collide (LG_BBox *bbox1[], LG_BBox *bbox2[])
Lines3D_VB	lg_l3d_vb_from_bbox (LG_BBox bbox, LG_Color_u c)
void	lg_bbox_info (LG_BBox *bbox)
LG_BSphere	lg_bsphere (float x_center, float y_center, float z_center, float radius)
LG_BSphere	lg_bsphere_from_bbox (LG_BBox bbox)
LG_BSphere	lg_bsphere_from_mesh (LG_Mesh *mesh)
zboolean	lg_bspheres_collide (LG_BSphere *bsphere1, LG_BSphere *bsphere2)
zboolean	lg_bsphere_sets_collide (LG_BSphere *bsphere1[], LG_BSphere *bsphere2[])
void	lg_bsphere_info (LG_BSphere bsphere)

Detailed Description

 === 3D collision detection funcs and algos ===

 Using so far:
 - Bounding boxes
 - Bounding spheres

Function Documentation

lg_bbox()

LG_BBox lg_bbox	(	float	min_x,
		float	max_x,
		float	min_y,
		float	max_y,
		float	min_z,
		float	max_z
	)

Create an axis-aligned bounding box (AABB)

Parameters

min_x
max_x;
min_y
max_y
min_z
max_z

Returns

A new axis-aligned LG_BBox

lg_bbox_from_cuboid()

LG_BBox lg_bbox_from_cuboid

(

LG_Cuboid *

cuboid

)

Return an axis-aligned bounding box from a cuboid

y ^
  |
  |   v[7]------v[6]
  v[3]------v[2] |
  |    |     |   |
  |    |     |   |
  |   v[4]---|--v[5]
  v[0]------v[1]------>
                      x

Parameters

cub	Pointer to a LG_Cuboid

Returns

A new axis-aligned LG_BBox

lg_cuboid_from_bbox()

LG_Cuboid lg_cuboid_from_bbox	(	LG_BBox	bbox,
		LG_Color_u	c
	)

Return a cuboid from a bounding box and color

y ^
  |
  |   v[7]------v[6]
  v[3]------v[2] |
  |    |     |   |
  |    |     |   |
  |   v[4]---|--v[5]
  v[0]------v[1]------>
                      x

Parameters

bbox	A LG_BBox
c	A LG_Color_u

Returns

A new colored LG_Cuboid

lg_bbox_from_mesh()

LG_BBox lg_bbox_from_mesh

(

LG_Mesh *

mesh

)

Return bounding box of a mesh

(pretty dumb func, only return mesh->bbox)

Parameters

mesh	Pointer to a LG_Mesh

Returns

A new LG_BBox

lg_bbox_transform()

LG_BBox lg_bbox_transform	(	LG_BBox	bbox,
		mat4_t	matrix
	)

Transform bounding box with STR matrix - original bounding box is not modified

Parameters

bbox	A LG_BBox
matrix	A mat4_t matrix

Returns

A new LG_BBox

lg_bbox_get_center()

vec3_t lg_bbox_get_center

(

LG_BBox *

bbox

)

Get center of a bounding box

Parameters

bbox	Pointer to a LG_BBox

Returns

Center of bounding box

lg_bboxes_collide()

zboolean lg_bboxes_collide	(	LG_BBox *	bbox1,
		LG_BBox *	bbox2
	)

Test if 2 axis-aligned bounding boxes collide

Parameters

bbox1	Pointer to an axis-aligned LG_BBox
bbox2	Pointer to an axis-aligned LG_BBox

Returns

TRUE if the boxes overlap, FALSE otherwise

lg_bbox_sets_collide()

zboolean lg_bbox_sets_collide	(	LG_BBox *	bbox1[],
		LG_BBox *	bbox2[]
	)

Test if 2 axis-aligned bounding box sets collide

Parameters

bbox1	Array of pointers to axis-aligned LG_BBox, NULL terminated
bbox2	Array of pointers to axis-aligned LG_BBox, NULL terminated

Returns

TRUE if the bbox sets overlap, FALSE otherwise

lg_l3d_vb_from_bbox()

Lines3D_VB lg_l3d_vb_from_bbox	(	LG_BBox	bbox,
		LG_Color_u	c
	)

Create and fill a Lines3D_VB (line set vertex buffer and num of vertices) from a bounding box

 Draw with glDrawArrays(GL_LINE, 0, LG_CUBOID_LINES_N_VERTICES or n_vertices)
 (if n_vertices > 0)

The vertex buffer is a static one (static array)

y ^
  |
  |   v[7]------v[6]
  v[3]------v[2] |
  |    |     |   |
  |    |     |   |
  |   v[4]---|--v[5]
  v[0]------v[1]------>
                      x

Parameters

bbox	A LG_BBox
c	A LG_Color_u

Returns

A new Lines3D_VB - n_vertices set to 0 on error

lg_bbox_info()

void lg_bbox_info

(

LG_BBox *

bbox

)

Print out bbox info

Parameters

bbox	Pointer to a LG_BBox

lg_bsphere()

LG_BSphere lg_bsphere	(	float	x_center,
		float	y_center,
		float	z_center,
		float	radius
	)

Create a bounding sphere

Parameters

x_center;
y_center;
z_center;
radius

Returns

A new LG_BSphere

lg_bsphere_from_bbox()

LG_BSphere lg_bsphere_from_bbox

(

LG_BBox

bbox

)

Compute bounding sphere from bounding box

Parameters

bbox

A LG_BBox

Returns

A new LG_BSphere

lg_bsphere_from_mesh()

LG_BSphere lg_bsphere_from_mesh

(

LG_Mesh *

mesh

)

Compute bounding sphere of a mesh

Parameters

mesh	Pointer to a LG_Mesh

Returns

A new LG_BSphere

lg_bspheres_collide()

zboolean lg_bspheres_collide	(	LG_BSphere *	bsphere1,
		LG_BSphere *	bsphere2
	)

Test if 2 bounding spheres collide

Parameters

bsphere1	Pointer to a LG_BSphere
bsphere2	Pointer to a LG_BSphere

Returns

TRUE if the spheres overlap, FALSE otherwise

lg_bsphere_sets_collide()

zboolean lg_bsphere_sets_collide	(	LG_BSphere *	bsphere1[],
		LG_BSphere *	bsphere2[]
	)

Test if 2 bounding sphere sets collide

Parameters

bsphere1	Array of pointers to LG_BSphere, NULL terminated
bsphere2	Array of pointers to LG_BSphere, NULL terminated

Returns

TRUE if the sphere sets overlap, FALSE otherwise

lg_bsphere_info()

void lg_bsphere_info

(

LG_BSphere

bsphere

)

Print out bsphere info

Parameters

bsphere

A LG_BSphere